When a diesel engine is below a certain threshold temperature, it can be difficult or impossible to start the engine until the engine is heated. When a vehicle is being used, the natural action of the engine generally maintains the engine at a sufficiently high temperature to operate; however, in typical daily use, vehicles are not utilized continuously for an entire 24-hour period. If a vehicle is left outside or otherwise exposed to sufficiently cold temperatures, the vehicle will not be usable after a certain period of time because the engine will be too cold to start. Therefore, many diesel engines are installed with an electrical block heater that is configured to pre-heat the cylinder block of the engine when activated. Many commercial trucking businesses, public transit bus systems, and other entities that own vehicles with diesel engines (especially those located in colder climates) activate the block heaters of their vehicles either every night or on nights that are expected to be especially cold so that the engines of their vehicles are pre-heated and ready to start the following morning. Having the block heaters running continuously all night generally wastes fuel or electricity though because the length of time required for a block heater to fully pre-heat an engine is less than the length of time that the block heaters are generally left on, even in exceptionally cold climates. The wasted fuel or electrical energy results in substantial excess costs, which only increases with the number of vehicles in the fleet that require pre-heating. Furthermore, in situations where employees are expected to activate the block heaters of the vehicles themselves when especially cold temperatures are imminent, unexpectedly cold temperatures or human error can result in substantial productivity losses when the vehicles' engines are too cold to start for the subsequent use.
While several devices have been made and used, it is believed that no one prior to the inventors has made or used the device described in the appended claims.